diff --git a/src/requirements.txt b/src/requirements.txt
index 97e0e95..4514dc2 100644
--- a/src/requirements.txt
+++ b/src/requirements.txt
@@ -18,4 +18,4 @@ websocket-client==1.7.0
 websockets>=15.0.0
 tomli
 hypothesis
-mutmut>=2.4.4
+mutmut==2.4.4